Raloxifene is described in U.S. Pat. No. 4,418,068 and is known to be effective in treating the symptoms of post menopausal syndrome, particularly osteoporosis. Indeed, raloxifene hydrochloride was approved for marketing as a preventative treatment for osteoporosis by the U.S. Food and Drug Administration in late 1997.
Raloxifene hydrochloride has the following structure: ##STR1## Heretofore, the administration of raloxifene hydrochloride has generally been accomplished orally, i.e., by ingestion of tablets or capsules.
The determination of the lowest effective dose for a pharmaceutical agent is a goal generally of clinical trials. The delivery route and/or formulation of a particular pharmaceutical can significantly effect the size of the lowest effective dose. Administering the least amount of drug which provides the desired effect tends to minimize the possibility of any undesirable side-effects attributed to that pharmaceutical and further provides economic benefits to the drug manufacturer and consumer.
In most cases, relative to oral routes of delivery, respiratory and/or nasal delivery of a drug results in lower blood levels of the pharmaceutical in the recipient. Thus, the lowest effective dose for respiratory tract and nasal delivery is usually higher than for oral delivery. Furthermore, delivery of pharmaceuticals by inhalation into the lungs, or through the nose, is not common because the inhalation of some pharmaceuticals negatively alters the breathing parameters of the recipient.